TY - JOUR
T1 - Numerical Evaluation on Mechanical Behavior of No-Insulation REBCO Pancake Coils in Small-Scale Model of Skeleton Cyclotron
AU - Miyake, Yuta
AU - Nakai, Yuki
AU - Inoue, Ryota
AU - Kim, Seok Beom
AU - Ueda, Hiroshi
AU - Noguchi, So
AU - Watanabe, Tomonori
AU - Nagaya, Shigeo
AU - Fukuda, Mitsuhiro
AU - Ishiyama, Atsushi
N1 - Funding Information:
This work was supported in part by the JSPS Grant-in-Aid for Scientific Research (S) under Grant 18H05244.
Publisher Copyright:
© 2002-2011 IEEE.
PY - 2022/9/1
Y1 - 2022/9/1
N2 - We are developing a high-temperature superconducting (HTS) air-core compact cyclotron, named Skeleton Cyclotron (Ueda et al. 2013), (Ueda et al. 2019), that can accelerate various particles and variable energy for radioisotope (RI) production. The coil system of Skeleton Cyclotron consists of circular main coils and noncircular sector coils which are wound by REBa2Cu3O6+δ (REBCO) tape applied no-insulation (NI) winding technique for both high current densities and thermal stabilities. The electromagnetic and thermal behaviors in NI coil differs from those in conventional insulated coils during charging, discharging, and quenching. Therefore, it is necessary to investigate the mechanical behavior and reinforcement structure of multiple NI coils in Skeleton Cyclotron. In this study, we report on the numerical evaluation of mechanical properties of NI REBCO coils in Skeleton Cyclotron at charging and quenching considering the current distributions and electromagnetic stresses unique to NI coils. In the quenching process, the radial current in a quenching pancake of the sector coil became dominant, resulting in generating the rotating force and non-symmetric deformation. YOROI-coil (Y-based oxide superconductor and reinforcing outer integrated coil) structure is effective for the additional magnetic stress.
AB - We are developing a high-temperature superconducting (HTS) air-core compact cyclotron, named Skeleton Cyclotron (Ueda et al. 2013), (Ueda et al. 2019), that can accelerate various particles and variable energy for radioisotope (RI) production. The coil system of Skeleton Cyclotron consists of circular main coils and noncircular sector coils which are wound by REBa2Cu3O6+δ (REBCO) tape applied no-insulation (NI) winding technique for both high current densities and thermal stabilities. The electromagnetic and thermal behaviors in NI coil differs from those in conventional insulated coils during charging, discharging, and quenching. Therefore, it is necessary to investigate the mechanical behavior and reinforcement structure of multiple NI coils in Skeleton Cyclotron. In this study, we report on the numerical evaluation of mechanical properties of NI REBCO coils in Skeleton Cyclotron at charging and quenching considering the current distributions and electromagnetic stresses unique to NI coils. In the quenching process, the radial current in a quenching pancake of the sector coil became dominant, resulting in generating the rotating force and non-symmetric deformation. YOROI-coil (Y-based oxide superconductor and reinforcing outer integrated coil) structure is effective for the additional magnetic stress.
KW - Cyclotrons
KW - high-temperature
KW - no-insulation
KW - superconducting magnets
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U2 - 10.1109/TASC.2022.3163693
DO - 10.1109/TASC.2022.3163693
M3 - Article
AN - SCOPUS:85127487597
SN - 1051-8223
VL - 32
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
IS - 6
M1 - 4603905
ER -